Recently, various devices have been proposed for regenerating the sight (vision) of a blind patient. For instance, there is proposed a device for regenerating the sight of a patient by imparting electric stimulus from an optic papilla of the blind patient (see US 2006/0058857A (WO 2004/049986A)).
In the device arranged to electrically stimulate nerve fibers by an electrode implanted (inserted) in the optic papilla as mentioned above, it is important that the electrode is stably implanted in the optic papilla for a long term without coming off. In the case where a plurality of electrodes is implanted, it is preferable to discriminate them individually.